1. Field of the Invention
This invention relates generally to door fasteners. It relates particularly to a chain-type safety door latch which can be simply and quickly disengaged in the event of an emergency.
2. Prior Art
Numerous attempts have been made over the years to provide a safety door latch to prevent unlawful and undesired entry into dwellings, hotel rooms, and the like, and a number of devices are currently available on the market for purchase and use by the public. Notwithstanding the efficacy of these devices, they are all found wanting in one most important aspect, viz., they are not simply and quickly disengagable in the event of a fire or other emergency. That is to say, safety is provided by preventing unwanted entry into a room, but safety is not provided in the case of a hurried egress from the room, as in an emergency brought about by fire, unexpected illness, accident, etc. In particular, the safety chain, which keeps the intruder out, also keeps the occupant in, as it cannot be simply and quickly disengaged (especially by the elderly and the infirm) during a time of crisis.
The closest art known to applicants, viz., U.S. Pat. Nos. 4,472,153 and 4,296,957, will not obviate the problem, as the complicated devices disclosed therein do not provide for quick and simple disengagement of the safety latch, in order to allow rapid egress.